Rosette Cutting Speed

Drill press RPMs tend to be too slow for great success with machining rosettes, especially in difficult wood. May 21, 2009

QuestionI have aquired my first job that calls for cutting rosettes. I am attempting to cut a 2 3/4 rosette into red oak. I am having some trouble with chatter and chip out. What is a good spindle speed to use for this? I started with a slow 400 rpm and that was terrible. I next went to the opposite end of the spectrum, unsure of the speed but it sounded like an airplane about to take off. That was too fast. I slowed it down, and once the cutter gets its whole surface cutting, it seems fair, but still not a very smooth cut. I am using a carbide blade. In this case it was purchased from woodcraft, I couldn’t find that particular design anywhere else.

Forum Responses(Furniture Making Forum)
From contributor G:Might just be your drill quill isn't stable enough to hold itself steady enough to get a descent cut.

From the original questioner:I will try mounting it in my mortising machine. Maybe that will help. I also read to freeze the boards first. I wonder if that actually would help.

I couldn’t mount the cutter in my mortising machine, so I kept trying to use the drill press. It is a good one (floor stand, 500 pounds). It should be stable enough, but it was just no good. That is the end of my rosette cutting - never again, unless someone can tell me the trick. I did get enough to finish my job though. Just by luck.

From contributor G:Try this. If you have a spindle lock, clamp it down, not quite tight enough to prevent the handle from moving down, but tight enough to make the spindle stiff. It can't hurt to try.
From contributor D:If you have a jaw chuck for your lathe you could give that a go. Rosette cutter in the drill type head, locked. Block in the jaws, spinning.
From contributor S:I believe there is no drill press heavy enough, in common use, to make rosettes "as advertised". This tooling bloomed about 15 years ago and was everywhere, and now you hardly see it - a good clue to the fact that it does not work well. One way to do this is in a lathe (again, a heavy duty type). Spin the blank and advance the tailstock with the cutter in it. This will require a Morse taper on the cutter, but is usually solid enough to make it work. C G Schmidt makes a rosette cutting machine that does a good job.
From contributor R:I can't speak for all the tooling out there. Typically you need high rpm's for this operation. Most drill presses will not turn fast enough. About 5000rpm- modified a heavy duty delta years ago to do just that (while waiting for a dedicated machine) and it worked ok. You will need a machine such as Schmidt sells if you are doing any amount of production.
From contributor K:The Woodcraft cutters he is talking about are designed for drill press cutting at low RPM. Oak is one of the worst woods to use with these cutters. The tighter the grain in the wood the better these cutters work.
From contributor R:Define "slow". Most drill presses are capable of from several hundred to 3000+ RPM, my point if you read the post, was you need to cut at the highest possible speed allowed by the tool and machine.
From contributor K:These cutters are made to run in the 300-600 rpm range. Different woods need different speeds in this range.
From contributor B:I cut mine at around 750 rpm. And very slowly lower it into the wood. My first and last ones were mahogany and red oak if that tells you anything. I'd figure 35-50% waste on oak. Have scraps on hand and try to stay out of the cathedral grain.
From the original questioner:I have now tried cutting very slow, 240 and 360 rpm and also as fast as the press will go (up around 3,500) as I have had the best luck with the high speed. Maybe just because of the grain pattern of the blocks I'm using , but the last five I did came out with very minimal chipping or tearout. I will be able to apply a very little bit of red oak putty and dye it. It comes out just a tad bit darker than the wood, so it just looks like a grain line. I still think my cutter is ground a bit off center but since its working fair, I will keep it.
From contributor K:If your cutter acts like it is a bit off center make sure your table is perfectly square with the drill head (lower the table and insert a rod into the chuck and use a square to check). An out of square table will cause the problem you are talking about.
From contributor H:I bought a metal milling machine to run my cutter in and it works well. This type of machine is way heavier than a drill press.
From contributor B:Very few drill presses give good results with rosette cutters. The mortising machine is a good option, but you'll need an extended chuck. For my general mortiser, I bought a chuck and a shaft to extend it beyond the case. The shaft is clamped into the machine's chuck and extends through so that the new chuck is below the casing where the square chisel normally sits. The absence of a quill mechanism means a much stiffer setup. The lack of vibration means much less tearing. Enco carries the parts you need or a good machine shop in your area can make up the shaft. The other option, depending on the style of the rosette is to cut it using router bits. A bit more time consuming, but with jigs you will save a lot of cleanup.
From contributor K:Here are a few things that I did, besides tighten the quill lock. Move the table up as high as it can go, to shorten the length that the quill comes down. I made a fixture that held and indexed the rosette blank, but had top fixture with a hole the size of the cutter body. When it is clamped down to the blank, it acts as a guide bushing for the cutter. A provision needs to be made for the chips to clear, so it can't be solid all of the way around the cutter. An air nozzle to blow out the chips and heat also helps.

Questions entered in the Knowledge Base Article comment form will not generate responses! A list of WOODWEB Forums can be found at WOODWEB's Site Map.

When you post your question at the Forum, be sure to include references to the Knowledge Base article that inspired your question. The more information you provide with your question, the better your chances are of receiving responses.

The editors, writers, and staff at WOODWEB try to promote safe practices.
What is safe for one woodworker under certain conditions may not be safe
for others in different circumstances. Readers should undertake the use
of materials and methods discussed at WOODWEB after considerate evaluation,
and at their own risk.